Study On The Application Of EPC In Nodular Cast Iron Production

The Lost Foam Casting is called LFC(or EPC).This technology has caused great changes in the foundry.It is well known for its characteristics,such as low cost,high productivity and good working environment,etc.The EPC has sprung up thousands of enterprises of different sizes after more than 30 years of rapid development in China.The output of evaporative pattern castings has leads the world.At present,the EPC has not constituted a integrated theory system at home and abroad,we still have no practice guideline.The quality of castings produced in EPC is uneven.Low qualification rate has become the choke point in the production of spheroidal graphite iron castings both here and abroad.According to incomplete survey of China Foundry Association,the average pass rate of ductile iron produce in EPC is only about 85%in China.Of course,some individual enterprises pass rate is less than 50%.As the output of lost foam casting increases in China every year,it will be widely applied in future.This paper has made detailed analysis and research on the entire process of spheroidal graphite cast iron by EPC.We can solve their problems,improve its comprehensive performance and accelerate application and promotion with the Appr-opriate scheme.According to the analysis of production status of domestic and foreign about the EPC,the carbon defect,flow mark and bad microstructures are the important mass defect.The main influencing factors including coating,white mold material,casting process and smelting process ware studied.The sopcial-purpose water-based paint of ductile iron can help casting to reduce the carbon defects and flow mark through the disposition of coating’s elements.The best expendable pattern after the research of EPS、STMMA、EPMMA can decrease free carbon.We can make the molten iron have a high-temperature spheroidization and inoculation treatment process.The shrinkage cavity and inclusions can be effectively eliminated by using the treatment of flexible cold iron,corundum filter,increase rate of cooling and solid pattern.It is stable to produce QT450-10,QT600-3 main bearing caps and blet roller with proper materials and special process through the research,the qualified rate has reached up to 96%.The defects,such as wrinkle,carbon defect and bad structure,were solved in production of nodular iron by EPC.It can enrich the quality control theory of nodular iron by EPC and it is better for promotion of EPC,...